1. Field of the Invention
The present invention relates generally to apparatus for lifting small vehicles such as riding mowers, lawn and garden tractors, all-terrain vehicles, and the like. In particular, the present invention relates to a simple, rugged apparatus for engaging and lifting one end of a small vehicle into an elevated position that allows a mechanic to safely access the undercarriage of the vehicle.
2. Discussion of Background
Small tractors--riding mowers, lawn tractors, garden tractors, and like vehicles--are becoming increasingly popular among homeowners as well as lawn care professionals. These small vehicles are used for cutting grass and brush, removing debris, tilling soil, plowing snow, and assorted hauling tasks around gardens, parks, and small farms.
Like their larger counterparts, these vehicles require routine servicing such as lubrication and/or oil changes, battery replacement, and removal and replacement of mower blades and other parts (belts, filters, etc.). Many of these tasks require access to the undercarriage of the vehicle, which is difficult due to the generally low clearance and correspondingly limited access space. For many vehicular service and maintenance procedures, it is advantageous to lift one end of the vehicle (or even the entire vehicle) above ground level so as to give the mechanic more clearance and better access to the undercarriage.
Riding mowers and other small tractors typically weigh at least 150 kg or more, so they are virtually impossible to lift into an elevated position unaided. Conventional automobile jacks are not suitable, because these are not designed to be used safely with smaller vehicles such as riding mowers. Similarly, ramps designed for use with automobiles have the wrong tilt angles for use with smaller vehicles. Tractor dealers and professional mechanics have suitable lift equipment and/or garages with oil pits for servicing vehicles; however, few individual homeowners or even lawn care professionals have access to oil pits or safe, reliable lifts.
Some operators simply tip a small tractor onto its side in order to expose the undercarriage; however, this practice is not recommended due to the unstable position of the tractor and the possibility of losing oil and other fluids from the engine compartment. Without a safe way to access the undercarriage, safety-conscious homeowners (and other users) must take their small tractors to a dealer or a professional mechanic for even such simple tasks as oil changes. This problem is also experienced by the owners and operators of golf carts and other small motorized vehicles.
Many different types of vehicular lifts, ramps, and other devices are available to consumers. A common problem with ramps is stability: unless the ramps are secured, they may shift when a vehicle is driven onto (or off) the ramps. One approach to stabilizing ramps is to add a fabric web that extends outwards from the ramp. In U.S. Pat. No. 5,118,081, Edelman discloses this type of inclined vehicular ramp, where the weight of the vehicle on the fabric web holds the web in position; the web in turn secures and positions the ramps to prevent them from sliding while the vehicle is being driven on (or off). Sparling's automotive ramps (U.S. Pat. No. 4,993,685) also include webs that extends forwardly of the ramps to align and secure them in position.
Snickers (U.S. Pat. No. 5,000,423) provides a small vehicle lift with a pair of ramps, each ramp including an angled portion and a pivotably mounted, user-operated lever which pulls the vehicle up the ramp. The lift is secured to the vehicle by straps, and can be folded for storage. Migliorati's rocking platform (U.S. Pat. No. 4,238,114) includes a pair of parallel longitudinal rails for supporting a vehicle, a pair of ramps, and a dihedron-shaped base with two bearing planes, one parallel to the support surface and the other inclined with respect to the surface. The platform can be rocked from a horizontal position (where the supporting structure rests on the parallel bearing plane) to an inclined position (where it rests on the inclined plane).
Fisher's frame and jack assembly (U.S. Pat. No. 3,779,517) includes a pair of pivotable ramps and raised ends to help keep the vehicle in position. The frame is raised and lowered by a hydraulic lift. The Mervine and Scott devices (U.S. Pat. No. 2,556,929 and 1,408,408, respectively) also include fixed and pivotable portions; Scott's workbench has a stop at one end to prevent a motorcycle from rolling forwards. Kauppi (U.S. Pat. No. 3,326,525) discloses a tilt up ramp with two legs and a stop. The ramp has two stable positions, one where the ramp is inclined and one where it is parallel to the ground. One of the legs acts as a fulcrum to pivot the ramp from the inclined position to the parallel position as the vehicle is driven onto it.
Additional types of lifting devices are shown by McDonald (U.S. Pat. No. 2,415,018), Stone (U.S. Pat. No. 4,549,721), and Allmon, et al., (U.S. Pat. No. 4,082,250). McDonald shows a device with a ramp and a curved saddle for engaging the axle of the vehicle. Stone describes a portable jack with a base frame having a pair of pivotable lifter arms that engage and lift the chassis of a riding mower. The arms are operated by an upwardly extending screw-actuated scissors jack. Allmon, et al. provide a lifting apparatus that allows one person to lift objects such as truck camper covers, boats, and mowers. The apparatus includes a vertical support with pair of inclined braces; a pivotable L-shaped support is mounted to the vertical support.
Despite the variety of vehicular ramps and lifts that are available to consumers, there is no known lifting apparatus that is suitable for use with small vehicles such as riding mowers, that can be readily adjusted for use with different sizes, models, and types of vehicles, and that is safe, easy to use, and reliable. There is a need for a vehicular lifting apparatus that is straightforward and cost-effective to manufacture, and that can be adjusted for use with a variety of different small vehicles.